| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Denmark | 6 | |
| #2 | Switzerland | 1 | |
| #3 | Germany | 1 | |
| #4 | Spain | 1 | |
| #5 | France | 1 | |
| #6 | United States | 1 |
| # | Industry | |
|---|---|---|
| #1 | Consumer goods |
| # | Technology | |
|---|---|---|
| #1 | Sound-producing devices |
| # | Name | Total Patents |
|---|---|---|
| #1 | Rosenkilde Hakon | 8 |
| #2 | Scharbau Julius | 4 |
| #3 | Hakon Rosenkilde | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US4028503A | Electromagnetic sound generator | |
| ES126309A1 | A new aperiodic electric switch system. |